Set default value (e.g. name, email etc) from database for logged in users

I want to be able to populate fields such as First Name, Last Name, Email address from the WP user database. It first glance, the Mapping Options/Field Mapping Type should do the trick, but User Fields are restricted to Register/Login forms only. I can't make any sense of this as the user fields are not available until after a user has logged in so how could the be using in a login/registration form?

Anyway, please support the use of user fields (and ACF fields) to set the default value in forms.